How to read wallet.dat in PHP?

I am trying to read content of wallet.dat in PHP and I have search around and it seems surprisingly no one has mention it before.

I have this code which I am trying to loop around all the key/values in wallet.dat but I only get one key, "main". I guess main seems to be logical db name. ( https://github.com/bitcoin/bitcoin/blob/v0.9.0/src/db.cpp#L260 ) Do anyone know why it only finds main and not other key/values? The wallet is unencrypted.

Code

Code:

<?php
print_r(dba_handlers(true));

$id = dba_popen("wallet.dat", "r", "db4");

if (!$id) {
    echo "dba_open failed\n";
    exit;
}

$key = dba_firstkey($id);
$keys = array();
while ($key != false) {
    $value = dba_fetch($key, $id);
    $keys[] = array($key, $value);
    $key = dba_nextkey($id);
}

print_r($keys);

dba_close($id);

Output

Code:

Array
(
    [db4] => Berkeley DB 4.8.24: (August 14, 2009)
)
Array
(
    [0] => Array
        (
            [0] => main
            [1] => 
        )

)

I ran this in XAMPP 1.7.3 which has PHP 5.3.1 and php_dba.dll